FIG. 4 is a sectional view schematically showing a conventional composite electronic component. The composite electronic component has surface-mounted component (hereinafter called “component”) 3, such as a semiconductor device requiring a control voltage, mounted on multi-layer wiring board (hereinafter called “board”) 1. On the surface of board 1, there are disposed power terminal electrodes (hereinafter called “electrodes”) 2, and component 3 is mounted so as to be connected with electrodes 2.
In some of such composite electronic components, a plurality of control voltages for synchronous control are applied to component 3. In such a case, the control of the composite electronic component is being simplified by dividing external connection power supply terminal 4, which is disposed on the lower face of board 1, into branch circuits. One of the branch circuits is routed within board 1. A composite electronic component as noted above is disclosed, for example, in Japanese Translation of PCT Publication No. H05-500136.
There has been an increasing demand for miniaturization of small wireless communications apparatuses such as those for use in mobile telephones and the wireless LAN. To meet such a demand, it is required to miniaturize the composite electronic components. Therefore, it becomes necessary to mount component 3 requiring various types of control on board 1. However, routed portion 5 of the power supply path within board 1 becomes a cause of unnecessary coupling with other circuit electrodes 6 disposed within board 1 in a high-frequency range. Thus, it is necessary to increase inter-electrode distances and this makes it difficult to miniaturize the composite electronic component.